Open Valley is an ONF member operating a 4G/5G Open RAN lab and R&D center based in Cairo, Egypt. They provide an end-to-end O-RAN compliant test environment to enable the testing and validation of a wide range of O-RAN use cases by vendors and operators. In addition they offer an xApp development environment for testing of xApps. Open Valley deploys multiple architectures which leverage ONF’s open source SD-RAN platform which is built on other field proven ONF open source platforms including OMEC and ONOS/µONOS.
“Open Valley selected ONF’s SD-RAN platform to deploy based on the project’s proven track record of xApp integration which was demonstrated as part of the Deutsche Telekom (DT) field trial. The DT field trial with SD-RAN successfully integrated open RAN components from AirHop, Facebook, Intel, Rimedo Labs and others,” said Ahmed Rady, founder, president and CEO, Open Valley. Also, “A key advantage to SD-RAN is that it has a fully-integrated RAN Simulator to enable integration and testing of xApps, specifically the ones that need system-level environment,” said Mina Awad, R&D department head, Open Valley.
Open Valley and the Information Technology Institute (ITI) collaborated on the first Open RAN lab test and demonstration in the MENA region, in April 2023, which showcased ONF’s SD-RAN RIC capabilities and xApp use cases.
Overview of Open Valley Open RAN Labs Configured with ONF’s SD-RAN
Open Valley operates two Open RAN labs which are built solely utilizing open source platforms for complete end-to-end network connectivity.
The lab which utilizes the SD-RAN platform (figure 1) consists of COTS servers with an OS Ubuntu 18.04 server. The first server has the CU/DU stack installed on a bare metal server, with the O-CU and O-DU from the OpenAirInterface5g project which provides a fully open source 4G/5G access network. The SD-RAN RIC is hosted in a vagrant VM based on the K8r cluster.
SD-RAN integrates ONF’s OMEC EPC (Open Mobile Evolved Core), a highly scalable full featured open source EPC. In OMEC, HSS, PCRF and the billing system are integrated, providing an advantage to OMEC over other open source EPCs. For the RU, the Software Defined Radio platform, USRP B210, is used as an RF frontend for the LTE interface. For the UE, a commercial UE with a programmable SIM is used. This architecture provides Open Valley with the ability to test S1AP, S1-U and E2AP messaging.
Figure 1 - Open Valley SD-RAN deployment
Figure 2, shows an ORAN deployment using Magma core and O-eNB from the srsRAN project and O-gNB from the Openairinterface5g project. In this architecture, Open Valley used the SD-RAN RIC with a multi-Radio Access Network that is 4G/5G ORAN compliant.
Figure 2 - ORAN deployment with Magma Core
Open Valley Open RAN Tests and Results
Open Valley assessed the 3GPP and O-RAN interface and protocols through aforementioned setups. Therefore, the team makes a commercial UE attach, 4G/5G and capture the protocol massaging e.g. S1-MME, S1-U, NGAP and NG-U. Also, capture the E2AP protocol with O-RAN compliant eNB, gNB, CU and DU. The full end-to-end Open RAN system integration tests were completed successfully as depicted in Table 1, which shows all the integration endpoints and associated interfaces.
Table 1 - Protocols testing successfully during integration
In addition, Table 2, shows the functional test used to assess the 4G/5G ORAN setups and the results.
Table 2 - Functional Test Results
SD-RAN is a fully-integrated platform for building 4G/5G ORAN networks. Open Valley uses SD-RAN to test and verify the compatibility of the xApp with the RIC as well as its operation using the integrated RANsimulator. The SD-RAN project, compared to the other ORAN software communities, overcomes a significant obstacle for xApp vendors in their journey to successfully build a PoC xApp. Table 3 below shows a comparison between ONOS-RIC from ONF, RIC from ORAN Software Community and FlexRIC from Eurecom.
Table 3 - Open Source RIC Platforms
Development and testing of xApps supporting associated Open RAN use cases require the establishment of a pre-production and test environment before commercial launch and field trials begin. Establishing such a pre-production environment is typically very costly, time consuming and requires a significant amount of effort for integration. ONF and Open Source communities offer pre-integrated platforms for testing purposes (plug and play) with very minimal integration effort, are less time consuming to deploy and very cost efficient. Open Valley did face some challenges related to the bug fixes and support but the ONF SD-RAN community team is very responsive and actively answered our issues enabling us to complete an end-to-end setup.